Investigators said the Franks Taxi driver picked up the robber on Portland Street about 3:20 a.m. Sunday. The man asked if he could be taken to Somersworth.

The robber then pulled out a black semi-automatic handgun while they were on Salmon Falls Road and told the driver to pull onto Haven Hill Road, where he demanded money.

The robber then fled on foot towards Salmon Falls Road.

The robber is described as a 6-foot-tall white man with a thin build, a goatee and an unspecified tattoo on his right forearm. He was last seen wearing a very puffy gray jacket, black pants, dark sneakers and gloves.

The victim was not harmed during the incident, police said.

Anyone with information regarding this incident is asked to call Officer Matt Leccacorvi at 330-7127 or call Rochester Crimeline at 335-6500.